A recent study sponsored by the John Templeton Foundation found a dramatic gap between the gratitude people say they feel and what they express. In the large and demographically balanced survey, fully 90 percent of respondents said they were grateful for their immediate family, and 87 percent were grateful for their close friends. But when it came to expressing it, the numbers dropped almost in half. Only 52 percent of women and 44 percent of men said they express gratitude on a regular basis.

So why the big gap? Several factors come into play. Many people assume that those close to them already know how they feel, so they don’t need to state their appreciation. They are, of course, quite wrong. About 50 percent of women said they wished their husbands or partners would express more appreciation for what they did. Men, in particular, may feel that their actions are expression enough. In focus groups, some men said that they didn’t have to tell their wives they were grateful to them—they showed it by their actions. But reading those actions wasn’t always clear since they included things from cuddling on the couch to filling their cars with gas.

Some people—again, men in particular—may also worry that an expression of gratitude suggests weakness. They want to believe that they have achieved on their own, so why admit that someone else has helped? Another factor may be a fear of obligation. If they thank someone for a kindness, thereby recognizing it, are they then required to reciprocate? Interestingly, gratitude doesn’t work that way at all. People who are thanked and feel appreciated are more likely to continue their positive actions—not expect something in return.

About 60 percent of the people in the survey said they express gratitude in order to make themselves feel better. Those who shy away from gratitude aren’t proving their own strength—they are simply losing out.